愛玉，薁蕘: Calling All Jelly Bellies
Taiwanese jelly dessert how-to and a new Ai Yu Jelly Kit
This week, I’m reflecting on my favorite form of matter: jelly. I dialed in a handful of Taiwanese jelly dessert recipes this month and am sharing my notes, appealing to that deepest part of your psyche that enjoys the pursuit of all things jiggly. I also reflect a bit on the naming of Taiwan’s favorite dessert, Ai Yu Jelly, and what that might reveal about its roots in Taiwanese culture.
Also, did you know that Ai Yu was once voted Taiwan’s most popular summer snack? We just released a new Ai Yu Jelly Kit that has everything you need to make it at home, including a sweet, little recipe booklet and a silkscreened box.
Once upon a time, I wanted to be... well, I don't know what I wanted to be, but I wanted to study chemistry—more specifically, the physics of chemical systems and how matter comes together. Fast forward to the end of a not-very-long story: I studied architecture instead, a large part of the reason I now write you long letters about Taiwanese food. But, I never lost my soft spot for the natural sciences.
One formative summer, I worked at a magnet lab, where supercooled electromagnets were used to spin up nuclei for magnetic resonance spectroscopy. I was young and mostly useless, but I did float paperclips on strings around the magnets when no one was looking (tip from my graduate research advisor), and I synthesized my very first jelly (ok, colloid), for use in spectroscopy experiments.
It's a visceral memory: I followed the procedure with the unconcerned abandon of a novice, and a clear, gelatinous mass appeared out of nowhere, behaving in unpredictable, non-Newtonian ways. I panicked, thinking "this can't be right," and threw it away. To my credit, it actually was right, so I had to make it again. And again, and again. And so my summer came and went.
I thought about this experience earlier this month, when I was working on Taiwanese jelly desserts for a pop up I did at Hamden General with Phoebe Tran of Bé Bếp, a Vietnamese food and culture project. Phoebe and her team carried the event, serving beautiful platters of wood-fired chicken, turmeric rice, and greens from Star Route Farm.
I supplemented with my favorite summer desserts from Taiwan, the kind you really don't get here in the States. We had over 100 people RSVP, and though most people shared, it was still the largest volume of jelly I’ve ever made, magnet lab notwithstanding.
While testing recipes for the event, I was reminded of the work I had done that summer at the lab, which was more prep and procedure and less capital-S-science: calculating ingredient ratios, practicing good technique, trusting the process, and conjuring something fat, friendly, and fractal. And doing it over and over.
Out of curiosity, I looked up a few papers on the nature of Ai Yu (Ficus pumila var. awkeotsang). Turns out there is quite a bit written on the physiochemical properties of the jelly, published in journals with such riveting titles as Food Hydrocolloids and Polymer Carbohydrates. One paper, Rheo-chemistry of gelation in aiyu (fig) jelly, investigates what is actually happening while it’s setting. One observation:
The physical properties of the gel produced can vary widely with the plant sub-variety and processing method. The maximum gel storage modulus can vary over two orders of magnitude, and the gelation time can vary by several hours.
Well, I could’ve told ya that, Wang, Geri, Chen, Huang, McKinley, et al!
Another paper specifically studies the handcraft of abrading the seeds in a rinse bag, and why that works. If you’re curious, Ai Yu Figs are unique in the world of biodegradable food hydrocolloids. The outer layer of its seeds contains a type of pectin known as LMP (low methoxyl pectin), which interacts with calcium ions to form a suspension known as an egg-box formation. Unlike other fruit pectins and coagulation agents, which require sugar or heat to set, the kind of pectin in Ai Yu requires only water with calcium ions present. An anomaly of the natural world.
Though making my desserts was certainly a craft and not a science, I felt a resonance with the authors of these papers, imagining their undergraduate researchers making lots and lots of Ai Yu Jelly and thinking they must have done it wrong. Or just eating it when no one was looking. The lemon slice in the figure above indicates that at least somebody knew what they were doing.
Back to the pop up: my favorite thing about cooking for lots of people is the opportunity to dial in a recipe. I was proud of how the jellies turned out—they felt straight out of Taiwan. In the spirit of my past and future self, I’m sharing my kitchen notes with you. Consider them a basis to experiment from. Go forth and create your own magical, hydrocolloidal, microscopically wiggly, edible soft matter at home. Scroll on.
But First, Introducing the Ai Yu Jelly Box Set
We’ve just launched a new Ai Yu Jelly Kit, complete with everything you need to make Ai Yu Jelly at home (except for the mineral water). It includes our Alishan Ai Yu Jelly seeds, a mesh rinsing bag, a recipe booklet featuring a photo by Cat Yeh, and a new, silkscreened box designed by o.oo in Taiwan. We still sell the seed packets and rinsing bags individually, so you can re-up as you need.
The Golden Ratios
Below, find my compiled kitchen notes, the foundation of my pop-up desserts this month. Proceed with confidence but also caution: these are loosely collected and haven’t been recipe tested by others. Use all your senses and adjust as you need. Channel the lab assistant within you.
Please be in touch with questions, if you have them, or share any outcomes or experiences with us @yunhaishop or @lisa.cheng.smith on IG.
Tips on Assembly
Taiwanese jelly desserts are often a mix-and-match, pick-and-choose experience. The customer picks out a base and a few toppings, which are composed together in a beautiful heap. For this pop up, I determined the mix, so an unfamiliar audience had some ground to stand on. Do as you please.
ice cubes or shaved ice (optional) + syrup + jelly + chewy toppings + lemon juice or other liquid add-ons + syrup again + condensed milk or cream + rules are made to be broken
WHAT I DID
Ai Yu Jelly Bowl
ai yu + boba pearls + taro balls + lemon juice + osmanthus syrup
Grass Jelly Bowl
grass jelly + almond bean curd + sweet potato balls + black sugar syrup + creamer
Proportion, position, layering, and form are all really important.
Think about the color and shape of the bowl to complement what will be in it. If you’re bedding with ice, put a layer of syrup over it so it doesn’t taste bland as it melts. Use large wide spoons for scooping jelly to leave it as whole as possible. Serve 15% more topping than your instinct tells you because abundance is key. Be liberal with the syrup, knowing that nothing here is all that sweet to begin with.
Ai Yu Jelly
A gelation of mineral water made from the pectin of Ai Yu fig seeds. True Ai Yu requires mineral water to gel, doesn’t need refrigeration to set, and won’t break down when heated. It lasts about 24 hours in the fridge, but use it sooner. Read all about the natural history of Ai Yu Jelly in this installment of the newsletter.
1 g of seeds : 78 ml of water when using Yun Hai Alishan Ai Yu Seeds
Measure out your seeds by weight, add them into the mesh rinsing bag, and tie off.
Rub and squeeze the bag under the water for five minutes, but also use sensory cues. When done, the liquid will turn a beautiful amber color and the rinsing bag will no longer feel slimy. If you use too many seeds or over-abrade, the jelly may be goopy.
Make two hours before serving for the optimal chill.
Hands and equipment must be clean and oil-free.
Ai Yu pectin gelates in the presence of calcium ions, so hard water is required. Test tap ahead of time or use Fiji or Evian water.
Best used within 2-8 hours of set.
For official Yun Hai instructions, click here.
Grass Jelly is the English name for all drinks/suspensions made from Mesona chinesis, a plant in the mint family. The plants are harvested then fermented like oolong tea for a year; it has a rooibos-like flavor.
To make Grass Jelly, first stew the herbs to make a tea. Use various methods to set the tea into jelly, with a wide range of resultant textures. Optionally, cook the grass jelly herb with lye water or baking soda for a more complete extraction process.
More info on the production of grass jelly in this installment of the newsletter.
Mesona (Grass Jelly) Tea
RATIO (based on 100 g grass jelly herb)
100 g grass jelly herb
3000 ml water
0.25 tsp lye water (kansui) or baking soda
160 g rock sugar
Wash the grass jelly herb in a large water bath and strain.
Put it in a large stockpot with water and lye water (or baking soda, if using).
Boil for 35-45 minutes, partially covered to reduce evaporation. After this time, check the liquid. Hold it up to a light in a clear glass. It should block out light. If not using lye water, boil for several hours or use a pressure cooker on high for 45 minutes.
Strain the liquid once or twice through a mesh strainer.
Put tea back into pot, add water to bring the overall level back to 3 L. Add rock sugar to the liquid and bring to a simmer, stirring until dissolved. Taste and adjust sweetness level..
Lye water is an alkaline substance used to add bounce to ramen noodles or to make alkaline zongzi. It helps break down the cell walls in the herb to extract it more fully and quickly. It’s optional: without it, you’ll need to boil for longer and the color may be lighter. Too much lye water, and the tea will have a bitter aftertaste.
For official Yun Hai instructions, click here.
Setting Grass Jelly
There are many ways to set Mesona Tea into Grass Jelly. The textures range from soft and slimy to bouncy and cubic. Gelatin, agar-agar, tapioca starch, and sweet potato starch can all be used. Sweet potato starch is the most traditional; tapioca starch is a bit more Q.
RATIO (based on 3000 ml grass jelly tea)
100 g tapioca or sweet potato starch
30 g cold water
Bring the grass jelly tea back to a boil.
Mix the tapioca starch with cold water and stir into a slurry.
Add the starch slurry into the boiling tea while stirring. Continue to stir and let the liquid come back up to a boil. Stir for a minute more, allowing the starch to cook through.
Pour the thickened tea into a mold or shallow dish. Pop or remove air bubbles with a spoon. Cover and refrigerate. It will take a few hours to cool and set.
Different brands of starch may set differently. Some experimentation may be needed.
Grass Jelly desserts can be quite loose, so don’t worry if your jelly isn’t set like jello. Accept the spectrum.
Sweet Potato and Taro Dice
This is one topping that defines Taiwanese desserts. Made from sweet potatoes, taro root, and more root starches, these squarish balls have a bouncy texture, and taste sweet and of the earth. Use all sweet potato starch for a softer, more traditional texture, or tapioca starch for something with a little more bounce. Be sure to wear gloves when handling uncooked taro root; raw, it contains an irritant.
SWEET POTATO RATIO (based on 200 g sweet potato)
200 g sweet potato
60 g tapioca starch + 10 g sweet potato starch (or use all sweet potato starch)
TARO RATIO (based on 200 g taro root)
200 g taro root (use large kind, not small)
20 g sugar
60 g tapioca starch + 10 g sweet potato starch (or use all sweet potato starch)
40 g of hot water
Peel, cut, and steam the root vegetables. Use the Tatung Electric Steamer or do it over the stove.
Sweet potato: Be careful not to over steam the sweet potato since it may absorb too much water. To avoid dripping condensation on the sweet potatoes while cooking, angle the cover of the steamer or wrap it in cloth.
Taro: Use gloves when handling. The taro will take a bit longer to steam. It is cooked when a toothpick comes out clean.
Mash the taro or sweet potato while hot. Prepare one at a time, leaving the other batch in the steamer to stay warm until ready to work.
While warm, sprinkle in the starch and sugar, and mix together. Add water to the taro (see note below). This is best done with your hands, gloves recommended. Incorporate all.
Sweet potato: Add a little more starch if the potatoes absorbed too much water during steaming.
Taro: Look for a crumbly pie crust texture. Slowly add 40 g of hot water and incorporate until the dough comes together.
When ready the dough should come away cleanly from the hand and bowl.
Break dough into two or three equal parts, set aside and cover.
One by one, roll each part into a log, then slice into smaller cylinders. Or, roll the dough into a thick disk and slice into a grid. The size of the dice is up to Chef, but generally 3/4” x 3/4”. The traditional form is not a ball but a rounded cylinder or rectangular prism.
Drop the diced dough into a high-walled container filled with tapioca starch. Shake and roll to coat. This will also soften the edges of the pieces.
If freezing, separate them on a cookie sheet and freeze for an hour to prevent sticking before consolidating into a container. Will stay good for a couple months, and can be cooked from frozen.
To cook, bring a large stockpot of water to boil. Cook the sweet potato and taro balls separately; they cook at different rates. Add the balls into the water, stir, and boil until they float. Remove them with a slotted spoon and place them into a container. Toss with a generous amount of granulated sugar, which will melt and turn into a syrup to prevent them from sticking. Use within 4 hours.
Almond Bean Curd
Also known as Almond Tofu, this dessert is a look-alike to tofu, though it’s actually more like almond Jello. Growing up, we made it with milk, sugar, a hit of almond extract, and gelatin or agar-agar. The original almond bean curd is something else entirely, made from the milk of Chinese southern sweet and northern bitter almonds, which are the pits of different types of apricots and have the fragrance of marzipan.
The northern style contains small amounts of cyanide, which denatures when heated. All northern bitter almonds that enter the United States have already been heated and are safe, but as a precaution don’t eat these raw. I mostly use southern almonds and throw a handful of the bitter ones in for fragrance, but if cyanide is too medieval, just use the southern sweet ones.
RATIO (for 1000 ml water)
200 g southern sweet almonds
33 g northern bitter almonds
1000 ml water
100 ml milk (if omitting, replace with water)
60 g rock sugar (or to taste)
110 g konjac jelly powder
Make almond milk from the almonds: Soak the almonds in 1000 ml of water for at least 4 hours. Blend the almonds and soaking water into a slurry and strain through a nut milk bag. Work in batches or as appropriate. Use a nut milk maker if you have one.
Combine the strained almond milk with the rock sugar and bring to a simmer. Stir until dissolved. Add in the milk.
Add the konjac jelly powder while continuously stirring. Stir until dissolved.
Pour into a square-edged shallow pan (like a square cake pan or baking dish). Remove/pop air bubbles with a spoon, cover, and let set in the refrigerator until gelled.
Cut into squares. Enjoy within 24 hours for best results.
I love enjoying boba in formats other than bubble tea. It can be added as toppings to cakes and flans, and (my favorite) shaved ice or other jelly desserts. I didn’t make these by hand, but because it’s hard to find a good brand I’m here to recommend E-fa (made in Taiwan). Instructions for preparing pre-made boba are notoriously hard to find, so I’ve included mine here. They are a little different than the instructions on the package.
1 cup of pearls
10 cups of water
Bring water to a rolling boil. (Pearls will dissolve on contact with the water if not boiling).
Add pearls and boil for 5 minutes, stirring frequently to prevent sticking.
Remove from heat, cover, and let sit for another 5 minutes.
Strain pearls and add to an ice bath for 30 seconds.
Strain pearls again and place into a high-walled container. Immediately saturate with black sugar syrup (see below) to prevent sticking.
Do not refrigerate. Use within 4-6 hours.
Osmanthus Honey Syrup
Osmanthus is an edible flower from an evergreen tree in the olive family. It has an apricot-like flavor, which best comes out when infused into honey or sugar syrup. Make a jar of osmanthus honey and dilute into syrup when needed for a dessert topping.
1 part dried osmanthus flowers
1 part honey
Fill a container halfway full with the dried flowers.
Add honey in to fill to the top.
Let sit room temperature for a few days to infuse.
To use as a syrup, dilute the osmanthus-infused honey 1:1 with warm water and stir or shake.
Taiwanese Black Sugar Syrup
Taiwanese black sugar is that signature sweet, rich flavor that characterizes bubble tea, but it’s used for so much more than that. It’s an unrefined sugar, made from cooking down sugar cane plants, and contains molasses and a whole host of minerals. It’s almost chocolate-y in vibe.
1 part Taiwanese black sugar
1 part water
Combine water and sugar in a saucepan.
Heat until simmering, stirring occasionally until sugar is dissolved.
Cool and keep in the fridge.
One more thing before I go. I’ve long wondered about the history of Ai Yu Jelly. The name holds some clues.
In a commonly cited history of Ai Yu jelly, the term Ai Yu 愛玉 dates back to mid-19th century. As it’s told, a merchant was passing through Dapu 大埔, a mountainous town in Chiayi 嘉義. When he stopped to drink from a stream, he noticed that areas of the water had become jelly. He traced the cause to fallen seeds from the fruit of nearby trees and collected some. The name allegedly comes from his daughter, who helped him sell the jelly throughout the countryside.
It’s likely that at least some of that actually happened, but it isn’t the whole of it. In Taiwanese Hokkien, Ai Yu Jelly is called 薁蕘 ò-giô. The characters are different than the Mandarin 愛玉, and has more to do with botany than a person’s name. The second character refers to grass—hinting at an alternate history of the human recognition of this plant. Using the Hokkien name as the basis for research, we uncovered a bit more on the Ai Yu Jelly origin story.
In 1871, Scottish photographer John Thomson documented a visit to indigenous Siraya people in in Kaohsiung 高雄. There, he tasted “magic jelly” and marveled at how seeds could suspend water (source: Mata Taiwan). And, some say that the Taiwanese Hokkien word for ai yu, ò-giô 薁蕘, comes from a Pingpu indigenous language. There are also deviations from ò-giô, such as tsí-á 子仔 in Tainan and phian-phau 偏拋 in some parts of Hsinchu. These stories and variation in naming suggest that Ficus pumila v. awkeotsang (scientifically named after ò-giô) has been part of indigenous food practice in Taiwan much longer than the documented origins of the jelly.
Thanks to our new Digital Producer, Amalissa Uytingco, for the research!
Feeling not so microscopically wiggly,
Lisa Cheng Smith 鄭衍莉
Written with research support by Amalissa Uytingco and editing help from Lillian Lin and Luke Miller. If you enjoyed this newsletter, please share it with friends and subscribe if you haven’t already. I email once a month, sometimes more, sometimes less. For more Taiwanese food, head to yunhai.shop, follow us on instagram and twitter, or view the newsletter archives.